At the American airport, the head of state was welcomed by the US officials.
"We haven't been notified at all" about the threat, Trump said as he welcomed the president of Uzbekistan to the White House, before adding "We haven't seen anything".
The two countries cooperate closely to secure the border with Afghanistan and to interdict the illicit movement of narcotics.
Assad meets with Putin in Russian Federation
Thursday's meeting was the latest in a series of conferences on military issues Putin chaired this week at his Black Sea retreat. Russian television broadcast short clips from the two men's discussion.
In a statement summarizing the meeting, White said Mattis and Mirziyoyev discussed mutual security interests and addressed emerging challenges. The US Administration called the visit of the president of Uzbekistan "historical". Uzbekistan also previously provided a logistical supply route for USA and North Atlantic Treaty Organisation forces into Afghanistan.
The high-level talks are expected to focus on cooperation issues, important global and regional issues. Both presidents expressed support for including Afghanistan in multilateral cooperation formats in Central Asia, the White House said. The two leaders are expected to discuss Afghanistan, trade and security cooperation.
The two leaders condemned extremism and worldwide terrorism, and vowed to strengthen cooperation against these common threats.